cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A329341 Length of nontrivial cycles under the ghost iteration A329201, as listed in the table A329342.

Original entry on oeis.org

3, 7, 3, 6, 5, 3, 3, 6, 9, 12, 5, 3, 3, 3, 3, 6, 3, 5, 4, 3, 3, 3, 3, 3, 6, 3, 5, 4, 11, 3, 3, 3, 3, 17, 3, 3, 6, 3, 3, 5, 11
Offset: 1

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Author

M. F. Hasler, Nov 10 2019

Keywords

Comments

A329201 consists of adding or subtracting the number A040115(n) whose digits are the difference between adjacent digits of n, depending on its parity. Repdigits A010785 are fixed points of this map, but some numbers enter nontrivial cycles. Sequence A329342 lists these cycles, ordered by their smallest member which is always listed first. This sequence gives the row lengths.

Examples

			a(1) = 3 is the length of the first cycle, (8290, 8969, 9102).
a(2) = 7 is the length of the next cycle, (17998,  24199,  21819,  20041,  22084,  21800, 20020).
a(3) = 3 = a(7) is the length of all members of the family starting with (21901, 23792, 25219) and continued by duplicating the initial digit of each term.
a(4) = 6 = a(8) is the length of all members of the family starting with (54503,  55656,  55767,  55978,  56399,  55039), extended as above.
a(5) = 5 = a(11) is the length of all members of the family starting with (87290,  88869,  88892,  88909,  89108), extended as above.
		

Crossrefs

Cf. A329342 (table of cycles), A329201, A329197 (analog for A329200), A329198.

Extensions

a(12) - a(41) from Scott R. Shannon, Nov 12 2019